Let's just clear up what cheating is:

If you’re doing something, anything, with someone and you don’t want your significant other to know about it,

That is cheating.

It doesn’t matter if you’re not kissing, touching, fucking, anything.

If you’re giving any piece of yourself to someone else you could potentially be involved with, whether it be a piece of your heart or mind, you are cheating.

You are trying to fill a void in your relationship.

This is cheating.